launchd/src/StartupItemContext.c

   1 /*
   2  * Copyright (c) 2002 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22
  23 #include <mach/mach.h>
  24 #include <mach/mach_error.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <unistd.h>
  28 #include <errno.h>
  29
  30 #include <servers/bootstrap.h>
  31
  32 int main(int argc, char *argv[])
  33 {
  34         mach_port_t root_bootstrap_port;
  35         kern_return_t ret;
  36 #if 0
  37         task_t init_task;
  38         int err;
  39 #endif
  40
  41         if (argc < 2) {
  42                 fprintf(stderr, "usage: %s executable [args...]\n", argv[0]);
  43                 exit(1);
  44         }
  45
  46         if (geteuid() != 0) {
  47                 fprintf(stderr, "%s: permission denied: must be run as root\n", argv[0]);
  48                 return(EPERM);
  49                 exit(1);
  50         }
  51
  52 #if 0
  53         /* get init's task port */
  54         ret = task_for_pid((mach_task_self)(), 1, &init_task);
  55         if (ret != KERN_SUCCESS) {
  56                 fprintf(stderr, "%s: task_for_pid() failed: permission denied\n",
  57                                 argv[0]);
  58                 exit(1);
  59         }
  60         /* extract its bootstrap port, which should be the root */
  61         ret = task_get_bootstrap_port(init_task, &root_bootstrap_port);
  62         if (ret != KERN_SUCCESS) {
  63                 fprintf(stderr, "%s: task_get_bootstrap_port() failed: %s\n",
  64                                 argv[0], mach_error_string(ret));
  65                 exit(2);
  66         }
  67 #else
  68         /*
  69          * Keep looping, getting out bootstrap's parent until it repeats, then we
  70          * know we are at the root/startupItem context.
  71          */
  72         {
  73                 mach_port_t cur_bootstrap;
  74
  75                 root_bootstrap_port = bootstrap_port;
  76                 do {
  77                         cur_bootstrap = root_bootstrap_port;
  78                         ret = bootstrap_parent(cur_bootstrap, &root_bootstrap_port);
  79                         if (ret == BOOTSTRAP_NOT_PRIVILEGED) {
  80                                 fprintf(stderr, "%s: must be run as root\n", argv[0]);
  81                                 exit(1);
  82                         }
  83                 } while (root_bootstrap_port != cur_bootstrap);
  84         }
  85 #endif
  86
  87         /* set that as our bootstrap port */
  88         ret = task_set_bootstrap_port(mach_task_self(), root_bootstrap_port);
  89         if (ret != KERN_SUCCESS) {
  90                 fprintf(stderr, "%s: task_set_bootstrap_port() failed: %s\n",
  91                                 argv[0], mach_error_string(ret));
  92                 exit(3);
  93         }
  94
  95         /* exec the program called for */
  96         execv(argv[1], &argv[1]); /* should not return */
  97         fprintf(stderr, "%s: exec failed: %s(%d)\n", argv[0], strerror(errno), errno);
  98         return(4);
  99 }